/*
 *
 *  *  Copyright 2014 Orient Technologies LTD (info(at)orientechnologies.com)
 *  *
 *  *  Licensed under the Apache License, Version 2.0 (the "License");
 *  *  you may not use this file except in compliance with the License.
 *  *  You may obtain a copy of the License at
 *  *
 *  *       http://www.apache.org/licenses/LICENSE-2.0
 *  *
 *  *  Unless required by applicable law or agreed to in writing, software
 *  *  distributed under the License is distributed on an "AS IS" BASIS,
 *  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  *  See the License for the specific language governing permissions and
 *  *  limitations under the License.
 *  *
 *  * For more information: http://www.orientechnologies.com
 *
 */

package com.orientechnologies.orient.core.serialization;

import com.orientechnologies.common.io.OIOException;
import com.orientechnologies.common.log.OLogManager;
import com.orientechnologies.common.util.OCommonConst;

/**
 * <p>
 * Encodes and decodes to and from Base64 notation.
 * </p>
 * <p>
 * Homepage: <a href="http://iharder.net/base64">http://iharder.net/base64</a>.
 * </p>
 * 
 * <p>
 * Example:
 * </p>
 * 
 * <code>String encoded = Base64.encode( myByteArray );</code> <br>
 * <code>byte[] myByteArray = Base64.decode( encoded );</code>
 * 
 * <p>
 * The <tt>options</tt> parameter, which appears in a few places, is used to pass several pieces of information to the encoder. In
 * the "higher level" methods such as encodeBytes( bytes, options ) the options parameter can be used to indicate such things as
 * first gzipping the bytes before encoding them, not inserting linefeeds, and encoding using the URL-safe and Ordered dialects.
 * </p>
 * 
 * <p>
 * Note, according to <a href="http://www.faqs.org/rfcs/rfc3548.html">RFC3548</a>, Section 2.1, implementations should not add line
 * feeds unless explicitly told to do so. I've got Base64 set to this behavior now, although earlier versions broke lines by
 * default.
 * </p>
 * 
 * <p>
 * The constants defined in Base64 can be OR-ed together to combine options, so you might make a call like this:
 * </p>
 * 
 * <code>String encoded = Base64.encodeBytes( mybytes, Base64.GZIP | Base64.DO_BREAK_LINES );</code>
 * <p>
 * to compress the data before encoding it and then making the output have newline characters.
 * </p>
 * <p>
 * Also...
 * </p>
 * <code>String encoded = Base64.encodeBytes( crazyString.getBytes() );</code>
 * 
 * 
 * 
 * <p>
 * Change Log:
 * </p>
 * <ul>
 * <li>v2.3.7 - Fixed subtle bug when base 64 input stream contained the value 01111111, which is an invalid base 64 character but
 * should not throw an ArrayIndexOutOfBoundsException either. Led to discovery of mishandling (or potential for better handling) of
 * other bad input characters. You should now get an IOException if you try decoding something that has bad characters in it.</li>
 * <li>v2.3.6 - Fixed bug when breaking lines and the final byte of the encoded string ended in the last column; the buffer was not
 * properly shrunk and contained an extra (null) byte that made it into the string.</li>
 * <li>v2.3.5 - Fixed bug in {@link #encodeFromFile} where estimated buffer size was wrong for files of size 31, 34, and 37 bytes.
 * </li>
 * <li>v2.3.4 - Fixed bug when working with gzipped streams whereby flushing the Base64.OutputStream closed the Base64 encoding (by
 * padding with equals signs) too soon. Also added an option to suppress the automatic decoding of gzipped streams. Also added
 * experimental support for specifying a class loader when using the
 * {@link #decodeToObject(java.lang.String, int, java.lang.ClassLoader)} method.</li>
 * <li>v2.3.3 - Changed default char encoding to US-ASCII which reduces the internal Java footprint with its CharEncoders and so
 * forth. Fixed some javadocs that were inconsistent. Removed imports and specified things like java.io.IOException explicitly
 * inline.</li>
 * <li>v2.3.2 - Reduced memory footprint! Finally refined the "guessing" of how big the final encoded data will be so that the code
 * does not have to create two output arrays: an oversized initial one and then a final, exact-sized one. Big win when using the
 * {@link #encodeBytesToBytes(byte[])} family of methods (and not using the gzip options which uses a different mechanism with
 * streams and stuff).</li>
 * <li>v2.3.1 - Added {@link #encodeBytesToBytes(byte[], int, int, int)} and some similar helper methods to be more efficient with
 * memory by not returning a String but just a byte array.</li>
 * <li>v2.3 - <strong>This is not a drop-in replacement!</strong> This is two years of comments and bug fixes queued up and finally
 * executed. Thanks to everyone who sent me stuff, and I'm sorry I wasn't able to distribute your fixes to everyone else. Much bad
 * coding was cleaned up including throwing exceptions where necessary instead of returning null values or something similar. Here
 * are some changes that may affect you:
 * <ul>
 * <li><em>Does not break lines, by default.</em> This is to keep in compliance with
 * <a href="http://www.faqs.org/rfcs/rfc3548.html">RFC3548</a>.</li>
 * <li><em>Throws exceptions instead of returning null values.</em> Because some operations (especially those that may permit the
 * GZIP option) use IO streams, there is a possiblity of an java.io.IOException being thrown. After some discussion and thought,
 * I've changed the behavior of the methods to throw java.io.IOExceptions rather than return null if ever there's an error. I think
 * this is more appropriate, though it will require some changes to your code. Sorry, it should have been done this way to begin
 * with.</li>
 * <li><em>Removed all references to System.out, System.err, and the like.</em> Shame on me. All I can say is sorry they were ever
 * there.</li>
 * <li><em>Throws NullPointerExceptions and IllegalArgumentExceptions</em> as needed such as when passed arrays are null or offsets
 * are invalid.</li>
 * <li>Cleaned up as much javadoc as I could to avoid any javadoc warnings. This was especially annoying before for people who were
 * thorough in their own projects and then had gobs of javadoc warnings on this file.</li>
 * </ul>
 * <li>v2.2.1 - Fixed bug using URL_SAFE and ORDERED encodings. Fixed bug when using very small files (~&lt; 40 bytes).</li>
 * <li>v2.2 - Added some helper methods for encoding/decoding directly from one file to the next. Also added a main() method to
 * support command line encoding/decoding from one file to the next. Also added these Base64 dialects:
 * <ol>
 * <li>The default is RFC3548 format.</li>
 * <li>Calling Base64.setFormat(Base64.BASE64_FORMAT.URLSAFE_FORMAT) generates URL and file name friendly format as described in
 * Section 4 of RFC3548. http://www.faqs.org/rfcs/rfc3548.html</li>
 * <li>Calling Base64.setFormat(Base64.BASE64_FORMAT.ORDERED_FORMAT) generates URL and file name friendly format that preserves
 * lexical ordering as described in http://www.faqs.org/qa/rfcc-1940.html</li>
 * </ol>
 * Special thanks to Jim Kellerman at <a href="http://www.powerset.com/">http://www.powerset.com/</a> for contributing the new
 * Base64 dialects.</li>
 * 
 * <li>v2.1 - Cleaned up javadoc comments and unused variables and methods. Added some convenience methods for reading and writing
 * to and from files.</li>
 * <li>v2.0.2 - Now specifies UTF-8 encoding in places where the code fails on systems with other encodings (like EBCDIC).</li>
 * <li>v2.0.1 - Fixed an error when decoding a single byte, that is, when the encoded data was a single byte.</li>
 * <li>v2.0 - I got rid of methods that used booleans to set options. Now everything is more consolidated and cleaner. The code now
 * detects when data that's being decoded is gzip-compressed and will decompress it automatically. Generally things are cleaner.
 * You'll probably have to change some method calls that you were making to support the new options format (<tt>int</tt>s that you
 * "OR" together).</li>
 * <li>v1.5.1 - Fixed bug when decompressing and decoding to a byte[] using <tt>decode( String s, boolean gzipCompressed )</tt>.
 * Added the ability to "suspend" encoding in the Output Stream so you can turn on and off the encoding if you need to embed base64
 * data in an otherwise "normal" stream (like an XML file).</li>
 * <li>v1.5 - Output stream pases on flush() command but does not do anything itself. This helps when using GZIP streams. Added the
 * ability to GZip-compress objects before encoding them.</li>
 * <li>v1.4 - Added helper methods to read/write files.</li>
 * <li>v1.3.6 - Fixed OutputStream.flush() so that 'position' is reset.</li>
 * <li>v1.3.5 - Added flag to turn on and off line breaks. Fixed bug in input stream where last buffer being read, if not completely
 * full, was not returned.</li>
 * <li>v1.3.4 - Fixed when "improperly padded stream" error was thrown at the wrong time.</li>
 * <li>v1.3.3 - Fixed I/O streams which were totally messed up.</li>
 * </ul>
 * 
 * <p>
 * I am placing this code in the Public Domain. Do with it as you will. This software comes with no guarantees or warranties but
 * with plenty of well-wishing instead! Please visit <a href="http://iharder.net/base64">http://iharder.net/base64</a> periodically
 * to check for updates or to contribute improvements.
 * </p>
 * 
 * @author Robert Harder
 * @author rob@iharder.net
 * @version 2.3.7
 */
public class OBase64Utils {

  /* ******** P U B L I C F I E L D S ******** */

  /** No options specified. Value is zero. */
  public final static int NO_OPTIONS = 0;

  /** Specify encoding in first bit. Value is one. */
  public final static int ENCODE = 1;

  /** Specify decoding in first bit. Value is zero. */
  public final static int DECODE = 0;

  /** Specify that data should be gzip-compressed in second bit. Value is two. */
  public final static int GZIP = 2;

  /** Specify that gzipped data should <em>not</em> be automatically gunzipped. */
  public final static int DONT_GUNZIP = 4;

  /** Do break lines when encoding. Value is 8. */
  public final static int DO_BREAK_LINES = 8;

  /**
   * Encode using Base64-like encoding that is URL- and Filename-safe as described in Section 4 of RFC3548:
   * <a href="http://www.faqs.org/rfcs/rfc3548.html">http://www.faqs.org/rfcs/rfc3548.html</a>. It is important to note that data
   * encoded this way is <em>not</em> officially valid Base64, or at the very least should not be called Base64 without also
   * specifying that is was encoded using the URL- and Filename-safe dialect.
   */
  public final static int URL_SAFE = 16;

  /**
   * Encode using the special "ordered" dialect of Base64 described here:
   * <a href="http://www.faqs.org/qa/rfcc-1940.html">http://www.faqs.org/qa/rfcc-1940.html</a>.
   */
  public final static int ORDERED = 32;

  /* ******** P R I V A T E F I E L D S ******** */

  /** Maximum line length (76) of Base64 output. */
  private final static int MAX_LINE_LENGTH = 76;

  /** The equals sign (=) as a byte. */
  private final static byte EQUALS_SIGN = (byte) '=';

  /** The new line character (\n) as a byte. */
  private final static byte NEW_LINE = (byte) '\n';

  /** Preferred encoding. */
  private final static String PREFERRED_ENCODING = "US-ASCII";

  private final static byte WHITE_SPACE_ENC = -5; // Indicates white space in
                                                  // encoding
  private final static byte EQUALS_SIGN_ENC = -1; // Indicates equals sign in
                                                  // encoding

  /* ******** S T A N D A R D B A S E 6 4 A L P H A B E T ******** */

  /** The 64 valid Base64 values. */
  /* Host platform me be something funny like EBCDIC, so we hardcode these values. */
  private final static byte[] _STANDARD_ALPHABET = { (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F',
      (byte) 'G', (byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N', (byte) 'O', (byte) 'P',
      (byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U', (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z',
      (byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g', (byte) 'h', (byte) 'i', (byte) 'j',
      (byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n', (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't',
      (byte) 'u', (byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z', (byte) '0', (byte) '1', (byte) '2', (byte) '3',
      (byte) '4', (byte) '5', (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) '+', (byte) '/' };

  /**
   * Translates a Base64 value to either its 6-bit reconstruction value or a negative number indicating some other meaning.
   **/
  private final static byte[] _STANDARD_DECODABET = { -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 0 - 8
      -5, -5, // Whitespace: Tab and Linefeed
      -9, -9, // Decimal 11 - 12
      -5, // Whitespace: Carriage Return
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 - 26
      -9, -9, -9, -9, -9, // Decimal 27 - 31
      -5, // Whitespace: Space
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 42
      62, // Plus sign at decimal 43
      -9, -9, -9, // Decimal 44 - 46
      63, // Slash at decimal 47
      52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // Numbers zero through nine
      -9, -9, -9, // Decimal 58 - 60
      -1, // Equals sign at decimal 61
      -9, -9, -9, // Decimal 62 - 64
      0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, // Letters 'A' through 'N'
      14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // Letters 'O' through 'Z'
      -9, -9, -9, -9, -9, -9, // Decimal 91 - 96
      26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, // Letters 'a' through 'm'
      39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // Letters 'n' through 'z'
      -9, -9, -9, -9, -9 // Decimal 123 - 127
      , -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 128 - 139
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 140 - 152
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 153 - 165
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 166 - 178
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 179 - 191
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 192 - 204
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 205 - 217
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 218 - 230
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 231 - 243
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9 // Decimal 244 - 255
  };

  /* ******** U R L S A F E B A S E 6 4 A L P H A B E T ******** */

  /**
   * Used in the URL- and Filename-safe dialect described in Section 4 of RFC3548:
   * <a href="http://www.faqs.org/rfcs/rfc3548.html">http://www.faqs.org/rfcs/rfc3548.html</a>. Notice that the last two bytes
   * become "hyphen" and "underscore" instead of "plus" and "slash."
   */
  private final static byte[] _URL_SAFE_ALPHABET = { (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F',
      (byte) 'G', (byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N', (byte) 'O', (byte) 'P',
      (byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U', (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z',
      (byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g', (byte) 'h', (byte) 'i', (byte) 'j',
      (byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n', (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't',
      (byte) 'u', (byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z', (byte) '0', (byte) '1', (byte) '2', (byte) '3',
      (byte) '4', (byte) '5', (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) '-', (byte) '_' };

  /**
   * Used in decoding URL- and Filename-safe dialects of Base64.
   */
  private final static byte[] _URL_SAFE_DECODABET = { -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 0 - 8
      -5, -5, // Whitespace: Tab and Linefeed
      -9, -9, // Decimal 11 - 12
      -5, // Whitespace: Carriage Return
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 - 26
      -9, -9, -9, -9, -9, // Decimal 27 - 31
      -5, // Whitespace: Space
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 42
      -9, // Plus sign at decimal 43
      -9, // Decimal 44
      62, // Minus sign at decimal 45
      -9, // Decimal 46
      -9, // Slash at decimal 47
      52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // Numbers zero through nine
      -9, -9, -9, // Decimal 58 - 60
      -1, // Equals sign at decimal 61
      -9, -9, -9, // Decimal 62 - 64
      0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, // Letters 'A' through 'N'
      14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // Letters 'O' through 'Z'
      -9, -9, -9, -9, // Decimal 91 - 94
      63, // Underscore at decimal 95
      -9, // Decimal 96
      26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, // Letters 'a' through 'm'
      39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // Letters 'n' through 'z'
      -9, -9, -9, -9, -9 // Decimal 123 - 127
      , -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 128 - 139
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 140 - 152
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 153 - 165
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 166 - 178
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 179 - 191
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 192 - 204
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 205 - 217
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 218 - 230
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 231 - 243
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9 // Decimal 244 - 255
  };

  /* ******** O R D E R E D B A S E 6 4 A L P H A B E T ******** */

  /**
   * I don't get the point of this technique, but someone requested it, and it is described here:
   * <a href="http://www.faqs.org/qa/rfcc-1940.html">http://www.faqs.org/qa/rfcc-1940.html</a>.
   */
  private final static byte[] _ORDERED_ALPHABET = { (byte) '-', (byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4',
      (byte) '5', (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E',
      (byte) 'F', (byte) 'G', (byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N', (byte) 'O',
      (byte) 'P', (byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U', (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y',
      (byte) 'Z', (byte) '_', (byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g', (byte) 'h',
      (byte) 'i', (byte) 'j', (byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n', (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r',
      (byte) 's', (byte) 't', (byte) 'u', (byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z' };

  /**
   * Used in decoding the "ordered" dialect of Base64.
   */
  private final static byte[] _ORDERED_DECODABET = { -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 0 - 8
      -5, -5, // Whitespace: Tab and Linefeed
      -9, -9, // Decimal 11 - 12
      -5, // Whitespace: Carriage Return
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 - 26
      -9, -9, -9, -9, -9, // Decimal 27 - 31
      -5, // Whitespace: Space
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 42
      -9, // Plus sign at decimal 43
      -9, // Decimal 44
      0, // Minus sign at decimal 45
      -9, // Decimal 46
      -9, // Slash at decimal 47
      1, 2, 3, 4, 5, 6, 7, 8, 9, 10, // Numbers zero through nine
      -9, -9, -9, // Decimal 58 - 60
      -1, // Equals sign at decimal 61
      -9, -9, -9, // Decimal 62 - 64
      11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, // Letters 'A' through 'M'
      24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, // Letters 'N' through 'Z'
      -9, -9, -9, -9, // Decimal 91 - 94
      37, // Underscore at decimal 95
      -9, // Decimal 96
      38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, // Letters 'a' through 'm'
      51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, // Letters 'n' through 'z'
      -9, -9, -9, -9, -9 // Decimal 123 - 127
      , -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 128 - 139
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 140 - 152
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 153 - 165
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 166 - 178
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 179 - 191
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 192 - 204
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 205 - 217
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 218 - 230
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 231 - 243
      -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9 // Decimal 244 - 255
  };

  /* ******** D E T E R M I N E W H I C H A L H A B E T ******** */

  /**
   * A {@link OBase64Utils.InputStream} will read data from another <tt>java.io.InputStream</tt>, given in the constructor, and
   * encode/decode to/from Base64 notation on the fly.
   * 
   * @see OBase64Utils
   * @since 1.3
   */
  public static class InputStream extends java.io.FilterInputStream {

    private boolean encode;       // Encoding or decoding
    private int     position;     // Current position in the buffer
    private byte[]  buffer;       // Small buffer holding converted data
    private int     bufferLength; // Length of buffer (3 or 4)
    private int     numSigBytes;  // Number of meaningful bytes in the buffer
    private int     lineLength;
    private boolean breakLines;   // Break lines at less than 80 characters
    private int     options;      // Record options used to create the stream.
    private byte[]  decodabet;    // Local copies to avoid extra method calls

    /**
     * Constructs a {@link OBase64Utils.InputStream} in DECODE mode.
     * 
     * @param in
     *          the <tt>java.io.InputStream</tt> from which to read data.
     * @since 1.3
     */
    public InputStream(java.io.InputStream in) {
      this(in, DECODE);
    } // end constructor

    /**
     * Constructs a {@link OBase64Utils.InputStream} in either ENCODE or DECODE mode.
     * <p>
     * Valid options:
     * 
     * <pre>
     *   ENCODE or DECODE: Encode or Decode as data is read.
     *   DO_BREAK_LINES: break lines at 76 characters
     *     (only meaningful when encoding)
     * </pre>
     * <p>
     * Example: <code>new Base64.InputStream( in, Base64.DECODE )</code>
     * 
     * 
     * @param in
     *          the <tt>java.io.InputStream</tt> from which to read data.
     * @param options
     *          Specified options
     * @see OBase64Utils#ENCODE
     * @see OBase64Utils#DECODE
     * @see OBase64Utils#DO_BREAK_LINES
     * @since 2.0
     */
    public InputStream(java.io.InputStream in, int options) {

      super(in);
      this.options = options; // Record for later
      this.breakLines = (options & DO_BREAK_LINES) > 0;
      this.encode = (options & ENCODE) > 0;
      this.bufferLength = encode ? 4 : 3;
      this.buffer = new byte[bufferLength];
      this.position = -1;
      this.lineLength = 0;
      this.decodabet = getDecodabet(options);
    } // end constructor

    /**
     * Reads enough of the input stream to convert to/from Base64 and returns the next byte.
     * 
     * @return next byte
     * @since 1.3
     */
    @Override
    public int read() throws java.io.IOException {

      // Do we need to get data?
      if (position < 0) {
        if (encode) {
          byte[] b3 = new byte[3];
          int numBinaryBytes = 0;
          for (int i = 0; i < 3; i++) {
            int b = in.read();

            // If end of stream, b is -1.
            if (b >= 0) {
              b3[i] = (byte) b;
              numBinaryBytes++;
            } else {
              break; // out of for loop
            } // end else: end of stream

          } // end for: each needed input byte

          if (numBinaryBytes > 0) {
            encode3to4(b3, 0, numBinaryBytes, buffer, 0, options);
            position = 0;
            numSigBytes = 4;
          } // end if: got data
          else {
            return -1; // Must be end of stream
          } // end else
        } // end if: encoding

        // Else decoding
        else {
          byte[] b4 = new byte[4];
          int i = 0;
          for (i = 0; i < 4; i++) {
            // Read four "meaningful" bytes:
            int b = 0;
            do {
              b = in.read();
            } while (b >= 0 && decodabet[b & 0x7f] <= WHITE_SPACE_ENC);

            if (b < 0) {
              break; // Reads a -1 if end of stream
            } // end if: end of stream

            b4[i] = (byte) b;
          } // end for: each needed input byte

          if (i == 4) {
            numSigBytes = decode4to3(b4, 0, buffer, 0, options);
            position = 0;
          } // end if: got four characters
          else if (i == 0) {
            return -1;
          } // end else if: also padded correctly
          else {
            // Must have broken out from above.
            throw new java.io.IOException("Improperly padded Base64 input.");
          } // end

        } // end else: decode
      } // end else: get data

      // Got data?
      if (position >= 0) {
        // End of relevant data?
        if ( /* !encode && */position >= numSigBytes) {
          return -1;
        } // end if: got data

        if (encode && breakLines && lineLength >= MAX_LINE_LENGTH) {
          lineLength = 0;
          return '\n';
        } // end if
        else {
          lineLength++; // This isn't important when decoding
                        // but throwing an extra "if" seems
                        // just as wasteful.

          int b = buffer[position++];

          if (position >= bufferLength) {
            position = -1;
          } // end if: end

          return b & 0xFF; // This is how you "cast" a byte that's
                           // intended to be unsigned.
        } // end else
      } // end if: position >= 0

      // Else error
      else {
        throw new java.io.IOException("Error in Base64 code reading stream.");
      } // end else
    } // end read

    /**
     * Calls {@link #read()} repeatedly until the end of stream is reached or <var>len</var> bytes are read. Returns number of bytes
     * read into array or -1 if end of stream is encountered.
     * 
     * @param dest
     *          array to hold values
     * @param off
     *          offset for array
     * @param len
     *          max number of bytes to read into array
     * @return bytes read into array or -1 if end of stream is encountered.
     * @since 1.3
     */
    @Override
    public int read(byte[] dest, int off, int len) throws java.io.IOException {
      int i;
      int b;
      for (i = 0; i < len; i++) {
        b = read();

        if (b >= 0) {
          dest[off + i] = (byte) b;
        } else if (i == 0) {
          return -1;
        } else {
          break; // Out of 'for' loop
        } // Out of 'for' loop
      } // end for: each byte read
      return i;
    } // end read

  } // end inner class InputStream

  /**
   * A {@link OBase64Utils.OutputStream} will write data to another <tt>java.io.OutputStream</tt>, given in the constructor, and
   * encode/decode to/from Base64 notation on the fly.
   * 
   * @see OBase64Utils
   * @since 1.3
   */
  public static class OutputStream extends java.io.FilterOutputStream {

    private boolean encode;
    private int     position;
    private byte[]  buffer;
    private int     bufferLength;
    private int     lineLength;
    private boolean breakLines;
    private byte[]  b4;             // Scratch used in a few places
    private boolean suspendEncoding;
    private int     options;        // Record for later
    private byte[]  decodabet;      // Local copies to avoid extra method calls

    /**
     * Constructs a {@link OBase64Utils.OutputStream} in ENCODE mode.
     * 
     * @param out
     *          the <tt>java.io.OutputStream</tt> to which data will be written.
     * @since 1.3
     */
    public OutputStream(java.io.OutputStream out) {
      this(out, ENCODE);
    } // end constructor

    /**
     * Constructs a {@link OBase64Utils.OutputStream} in either ENCODE or DECODE mode.
     * <p>
     * Valid options:
     * 
     * <pre>
     *   ENCODE or DECODE: Encode or Decode as data is read.
     *   DO_BREAK_LINES: don't break lines at 76 characters
     *     (only meaningful when encoding)
     * </pre>
     * <p>
     * Example: <code>new Base64.OutputStream( out, Base64.ENCODE )</code>
     * 
     * @param out
     *          the <tt>java.io.OutputStream</tt> to which data will be written.
     * @param options
     *          Specified options.
     * @see OBase64Utils#ENCODE
     * @see OBase64Utils#DECODE
     * @see OBase64Utils#DO_BREAK_LINES
     * @since 1.3
     */
    public OutputStream(java.io.OutputStream out, int options) {
      super(out);
      this.breakLines = (options & DO_BREAK_LINES) != 0;
      this.encode = (options & ENCODE) != 0;
      this.bufferLength = encode ? 3 : 4;
      this.buffer = new byte[bufferLength];
      this.position = 0;
      this.lineLength = 0;
      this.suspendEncoding = false;
      this.b4 = new byte[4];
      this.options = options;
      this.decodabet = getDecodabet(options);
    } // end constructor

    /**
     * Writes the byte to the output stream after converting to/from Base64 notation. When encoding, bytes are buffered three at a
     * time before the output stream actually gets a write() call. When decoding, bytes are buffered four at a time.
     * 
     * @param theByte
     *          the byte to write
     * @since 1.3
     */
    @Override
    public void write(int theByte) throws java.io.IOException {
      // Encoding suspended?
      if (suspendEncoding) {
        this.out.write(theByte);
        return;
      } // end if: supsended

      // Encode?
      if (encode) {
        buffer[position++] = (byte) theByte;
        if (position >= bufferLength) { // Enough to encode.

          this.out.write(encode3to4(b4, buffer, bufferLength, options));

          lineLength += 4;
          if (breakLines && lineLength >= MAX_LINE_LENGTH) {
            this.out.write(NEW_LINE);
            lineLength = 0;
          } // end if: end of line

          position = 0;
        } // end if: enough to output
      } // end if: encoding

      // Else, Decoding
      else {
        // Meaningful Base64 character?
        if (decodabet[theByte & 0x7f] > WHITE_SPACE_ENC) {
          buffer[position++] = (byte) theByte;
          if (position >= bufferLength) { // Enough to output.

            int len = OBase64Utils.decode4to3(buffer, 0, b4, 0, options);
            out.write(b4, 0, len);
            position = 0;
          } // end if: enough to output
        } // end if: meaningful base64 character
        else if (decodabet[theByte & 0x7f] != WHITE_SPACE_ENC) {
          throw new java.io.IOException("Invalid character in Base64 data.");
        } // end else: not white space either
      } // end else: decoding
    } // end write

    /**
     * Calls {@link #write(int)} repeatedly until <var>len</var> bytes are written.
     * 
     * @param theBytes
     *          array from which to read bytes
     * @param off
     *          offset for array
     * @param len
     *          max number of bytes to read into array
     * @since 1.3
     */
    @Override
    public void write(byte[] theBytes, int off, int len) throws java.io.IOException {
      // Encoding suspended?
      if (suspendEncoding) {
        this.out.write(theBytes, off, len);
        return;
      } // end if: supsended

      for (int i = 0; i < len; i++) {
        write(theBytes[off + i]);
      } // end for: each byte written

    } // end write

    /**
     * Method added by PHIL. [Thanks, PHIL. -Rob] This pads the buffer without closing the stream.
     * 
     * @throws java.io.IOException
     *           if there's an error.
     */
    public void flushBase64() throws java.io.IOException {
      if (position > 0) {
        if (encode) {
          out.write(encode3to4(b4, buffer, position, options));
          position = 0;
        } // end if: encoding
        else {
          throw new java.io.IOException("Base64 input not properly padded.");
        } // end else: decoding
      } // end if: buffer partially full

    } // end flush

    /**
     * Flushes and closes (I think, in the superclass) the stream.
     * 
     * @since 1.3
     */
    @Override
    public void close() throws java.io.IOException {
      // 1. Ensure that pending characters are written
      flushBase64();

      // 2. Actually close the stream
      // Base class both flushes and closes.
      super.close();

      buffer = null;
      out = null;
    } // end close

    /**
     * Suspends encoding of the stream. May be helpful if you need to embed a piece of base64-encoded data in a stream.
     * 
     * @throws java.io.IOException
     *           if there's an error flushing
     * @since 1.5.1
     */
    public void suspendEncoding() throws java.io.IOException {
      flushBase64();
      this.suspendEncoding = true;
    } // end suspendEncoding

    /**
     * Resumes encoding of the stream. May be helpful if you need to embed a piece of base64-encoded data in a stream.
     * 
     * @since 1.5.1
     */
    public void resumeEncoding() {
      this.suspendEncoding = false;
    } // end resumeEncoding

  } // end inner class OutputStream

  /** Defeats instantiation. */
  private OBase64Utils() {
  }

  /* ******** E N C O D I N G M E T H O D S ******** */

  /**
   * Returns one of the _SOMETHING_ALPHABET byte arrays depending on the options specified. It's possible, though silly, to specify
   * ORDERED <b>and</b> URLSAFE in which case one of them will be picked, though there is no guarantee as to which one will be
   * picked.
   */
  private final static byte[] getAlphabet(int options) {
    if ((options & URL_SAFE) == URL_SAFE) {
      return _URL_SAFE_ALPHABET;
    } else if ((options & ORDERED) == ORDERED) {
      return _ORDERED_ALPHABET;
    } else {
      return _STANDARD_ALPHABET;
    }
  } // end getAlphabet

  /**
   * Returns one of the _SOMETHING_DECODABET byte arrays depending on the options specified. It's possible, though silly, to specify
   * ORDERED and URL_SAFE in which case one of them will be picked, though there is no guarantee as to which one will be picked.
   */
  private final static byte[] getDecodabet(int options) {
    if ((options & URL_SAFE) == URL_SAFE) {
      return _URL_SAFE_DECODABET;
    } else if ((options & ORDERED) == ORDERED) {
      return _ORDERED_DECODABET;
    } else {
      return _STANDARD_DECODABET;
    }
  } // end getAlphabet

  /**
   * Encodes up to the first three bytes of array <var>threeBytes</var> and returns a four-byte array in Base64 notation. The actual
   * number of significant bytes in your array is given by <var>numSigBytes</var>. The array <var>threeBytes</var> needs only be as
   * big as <var>numSigBytes</var>. Code can reuse a byte array by passing a four-byte array as <var>b4</var>.
   * 
   * @param b4
   *          A reusable byte array to reduce array instantiation
   * @param threeBytes
   *          the array to convert
   * @param numSigBytes
   *          the number of significant bytes in your array
   * @return four byte array in Base64 notation.
   * @since 1.5.1
   */
  private static byte[] encode3to4(byte[] b4, byte[] threeBytes, int numSigBytes, int options) {
    encode3to4(threeBytes, 0, numSigBytes, b4, 0, options);
    return b4;
  } // end encode3to4

  /**
   * <p>
   * Encodes up to three bytes of the array <var>source</var> and writes the resulting four Base64 bytes to <var>destination</var>.
   * The source and destination arrays can be manipulated anywhere along their length by specifying <var>srcOffset</var> and
   * <var>destOffset</var>. This method does not check to make sure your arrays are large enough to accomodate <var>srcOffset</var>
   * + 3 for the <var>source</var> array or <var>destOffset</var> + 4 for the <var>destination</var> array. The actual number of
   * significant bytes in your array is given by <var>numSigBytes</var>.
   * </p>
   * <p>
   * This is the lowest level of the encoding methods with all possible parameters.
   * </p>
   * 
   * @param source
   *          the array to convert
   * @param srcOffset
   *          the index where conversion begins
   * @param numSigBytes
   *          the number of significant bytes in your array
   * @param destination
   *          the array to hold the conversion
   * @param destOffset
   *          the index where output will be put
   * @return the <var>destination</var> array
   * @since 1.3
   */
  private static byte[] encode3to4(byte[] source, int srcOffset, int numSigBytes, byte[] destination, int destOffset, int options) {

    byte[] ALPHABET = getAlphabet(options);

    // 1 2 3
    // 01234567890123456789012345678901 Bit position
    // --------000000001111111122222222 Array position from threeBytes
    // --------| || || || | Six bit groups to index ALPHABET
    // >>18 >>12 >> 6 >> 0 Right shift necessary
    // 0x3f 0x3f 0x3f Additional AND

    // Create buffer with zero-padding if there are only one or two
    // significant bytes passed in the array.
    // We have to shift left 24 in order to flush out the 1's that appear
    // when Java treats a value as negative that is cast from a byte to an int.
    int inBuff = (numSigBytes > 0 ? ((source[srcOffset] << 24) >>> 8) : 0)
        | (numSigBytes > 1 ? ((source[srcOffset + 1] << 24) >>> 16) : 0)
        | (numSigBytes > 2 ? ((source[srcOffset + 2] << 24) >>> 24) : 0);

    switch (numSigBytes) {
    case 3:
      destination[destOffset] = ALPHABET[(inBuff >>> 18)];
      destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
      destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f];
      destination[destOffset + 3] = ALPHABET[(inBuff) & 0x3f];
      return destination;

    case 2:
      destination[destOffset] = ALPHABET[(inBuff >>> 18)];
      destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
      destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f];
      destination[destOffset + 3] = EQUALS_SIGN;
      return destination;

    case 1:
      destination[destOffset] = ALPHABET[(inBuff >>> 18)];
      destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
      destination[destOffset + 2] = EQUALS_SIGN;
      destination[destOffset + 3] = EQUALS_SIGN;
      return destination;

    default:
      return destination;
    } // end switch
  } // end encode3to4

  /**
   * Performs Base64 encoding on the <code>raw</code> ByteBuffer, writing it to the <code>encoded</code> ByteBuffer. This is an
   * experimental feature. Currently it does not pass along any options (such as {@link #DO_BREAK_LINES} or {@link #GZIP}.
   * 
   * @param raw
   *          input buffer
   * @param encoded
   *          output buffer
   * @since 2.3
   */
  public static void encode(java.nio.ByteBuffer raw, java.nio.ByteBuffer encoded) {
    byte[] raw3 = new byte[3];
    byte[] enc4 = new byte[4];

    while (raw.hasRemaining()) {
      int rem = Math.min(3, raw.remaining());
      raw.get(raw3, 0, rem);
      OBase64Utils.encode3to4(enc4, raw3, rem, OBase64Utils.NO_OPTIONS);
      encoded.put(enc4);
    } // end input remaining
  }

  /**
   * Performs Base64 encoding on the <code>raw</code> ByteBuffer, writing it to the <code>encoded</code> CharBuffer. This is an
   * experimental feature. Currently it does not pass along any options (such as {@link #DO_BREAK_LINES} or {@link #GZIP}.
   * 
   * @param raw
   *          input buffer
   * @param encoded
   *          output buffer
   * @since 2.3
   */
  public static void encode(java.nio.ByteBuffer raw, java.nio.CharBuffer encoded) {
    byte[] raw3 = new byte[3];
    byte[] enc4 = new byte[4];

    while (raw.hasRemaining()) {
      int rem = Math.min(3, raw.remaining());
      raw.get(raw3, 0, rem);
      OBase64Utils.encode3to4(enc4, raw3, rem, OBase64Utils.NO_OPTIONS);
      for (int i = 0; i < 4; i++) {
        encoded.put((char) (enc4[i] & 0xFF));
      }
    } // end input remaining
  }

  /**
   * Serializes an object and returns the Base64-encoded version of that serialized object.
   * 
   * <p>
   * As of v 2.3, if the object cannot be serialized or there is another error, the method will throw an java.io.IOException.
   * <b>This is new to v2.3!</b> In earlier versions, it just returned a null value, but in retrospect that's a pretty poor way to
   * handle it.
   * </p>
   * 
   * The object is not GZip-compressed before being encoded.
   * 
   * @param serializableObject
   *          The object to encode
   * @return The Base64-encoded object
   * @throws java.io.IOException
   *           if there is an error
   * @throws NullPointerException
   *           if serializedObject is null
   * @since 1.4
   */
  public static String encodeObject(java.io.Serializable serializableObject) throws java.io.IOException {
    return encodeObject(serializableObject, NO_OPTIONS);
  } // end encodeObject

  /**
   * Serializes an object and returns the Base64-encoded version of that serialized object.
   * 
   * <p>
   * As of v 2.3, if the object cannot be serialized or there is another error, the method will throw an java.io.IOException.
   * <b>This is new to v2.3!</b> In earlier versions, it just returned a null value, but in retrospect that's a pretty poor way to
   * handle it.
   * </p>
   * 
   * The object is not GZip-compressed before being encoded.
   * <p>
   * Example options:
   * 
   * <pre>
   *   GZIP: gzip-compresses object before encoding it.
   *   DO_BREAK_LINES: break lines at 76 characters
   * </pre>
   * <p>
   * Example: <code>encodeObject( myObj, Base64.GZIP )</code> or
   * <p>
   * Example: <code>encodeObject( myObj, Base64.GZIP | Base64.DO_BREAK_LINES )</code>
   * 
   * @param serializableObject
   *          The object to encode
   * @param options
   *          Specified options
   * @return The Base64-encoded object
   * @see OBase64Utils#GZIP
   * @see OBase64Utils#DO_BREAK_LINES
   * @throws java.io.IOException
   *           if there is an error
   * @since 2.0
   */
  public static String encodeObject(java.io.Serializable serializableObject, int options) throws java.io.IOException {

    if (serializableObject == null) {
      throw new NullPointerException("Cannot serialize a null object.");
    } // end if: null

    // Streams
    java.io.ByteArrayOutputStream baos = null;
    java.io.OutputStream b64os = null;
    java.util.zip.GZIPOutputStream gzos = null;
    java.io.ObjectOutputStream oos = null;

    try {
      // ObjectOutputStream -> (GZIP) -> Base64 -> ByteArrayOutputStream
      baos = new java.io.ByteArrayOutputStream();
      b64os = new OBase64Utils.OutputStream(baos, ENCODE | options);
      if ((options & GZIP) != 0) {
        // Gzip
        gzos = new java.util.zip.GZIPOutputStream(b64os, 16384); // 16KB
        oos = new java.io.ObjectOutputStream(gzos);
      } else {
        // Not gzipped
        oos = new java.io.ObjectOutputStream(b64os);
      }
      oos.writeObject(serializableObject);
    } // end try
    catch (java.io.IOException e) {
      // Catch it and then throw it immediately so that
      // the finally{} block is called for cleanup.
      throw e;
    } // end catch
    finally {
      try {
        if (oos != null)
          oos.close();
      } catch (Exception e) {
      }
      try {
        if (gzos != null)
          gzos.close();
      } catch (Exception e) {
      }
      try {
        if (b64os != null)
          b64os.close();
      } catch (Exception e) {
      }
      try {
        if (baos != null)
          baos.close();
      } catch (Exception e) {
      }
    } // end finally

    // Return value according to relevant encoding.
    try {
      return new String(baos.toByteArray(), PREFERRED_ENCODING);
    } // end try
    catch (java.io.UnsupportedEncodingException uue) {
      // Fall back to some Java default
      return new String(baos.toByteArray());
    } // end catch

  } // end encode

  /**
   * Encodes a byte array into Base64 notation. Does not GZip-compress data.
   * 
   * @param source
   *          The data to convert
   * @return The data in Base64-encoded form
   * @throws NullPointerException
   *           if source array is null
   * @since 1.4
   */
  public static StringBuilder encodeBytes(final StringBuilder iOutput, final byte[] source) {
    if (source != null) {
      // Since we're not going to have the GZIP encoding turned on,
      // we're not going to have an java.io.IOException thrown, so
      // we should not force the user to have to catch it.
      try {
        iOutput.append(encodeBytes(source, 0, source.length, NO_OPTIONS));
      } catch (java.io.IOException ex) {
        assert false : ex.getMessage();
      }
    }
    return iOutput;
  }

  /**
   * Encodes a byte array into Base64 notation. Does not GZip-compress data.
   * 
   * @param source
   *          The data to convert
   * @return The data in Base64-encoded form
   * @throws NullPointerException
   *           if source array is null
   * @since 1.4
   */
  public static String encodeBytes(final byte[] source) {
    if (source == null)
      return null;

    // Since we're not going to have the GZIP encoding turned on,
    // we're not going to have an java.io.IOException thrown, so
    // we should not force the user to have to catch it.
    String encoded = null;
    try {
      encoded = encodeBytes(source, 0, source.length, NO_OPTIONS);
    } catch (java.io.IOException ex) {
      assert false : ex.getMessage();
    } // end catch
    assert encoded != null;
    return encoded;
  } // end encodeBytes

  /**
   * Encodes a byte array into Base64 notation.
   * <p>
   * Example options:
   * 
   * <pre>
   *   GZIP: gzip-compresses object before encoding it.
   *   DO_BREAK_LINES: break lines at 76 characters
   *     <i>Note: Technically, this makes your encoding non-compliant.</i>
   * </pre>
   * <p>
   * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or
   * <p>
   * Example: <code>encodeBytes( myData, Base64.GZIP | Base64.DO_BREAK_LINES )</code>
   * 
   * 
   * <p>
   * As of v 2.3, if there is an error with the GZIP stream, the method will throw an java.io.IOException. <b>This is new to
   * v2.3!</b> In earlier versions, it just returned a null value, but in retrospect that's a pretty poor way to handle it.
   * </p>
   * 
   * 
   * @param source
   *          The data to convert
   * @param options
   *          Specified options
   * @return The Base64-encoded data as a String
   * @see OBase64Utils#GZIP
   * @see OBase64Utils#DO_BREAK_LINES
   * @throws java.io.IOException
   *           if there is an error
   * @throws NullPointerException
   *           if source array is null
   * @since 2.0
   */
  public static String encodeBytes(byte[] source, int options) throws java.io.IOException {
    return encodeBytes(source, 0, source.length, options);
  } // end encodeBytes

  /**
   * Encodes a byte array into Base64 notation. Does not GZip-compress data.
   * 
   * <p>
   * As of v 2.3, if there is an error, the method will throw an java.io.IOException. <b>This is new to v2.3!</b> In earlier
   * versions, it just returned a null value, but in retrospect that's a pretty poor way to handle it.
   * </p>
   * 
   * 
   * @param source
   *          The data to convert
   * @param off
   *          Offset in array where conversion should begin
   * @param len
   *          Length of data to convert
   * @return The Base64-encoded data as a String
   * @throws NullPointerException
   *           if source array is null
   * @throws IllegalArgumentException
   *           if source array, offset, or length are invalid
   * @since 1.4
   */
  public static String encodeBytes(byte[] source, int off, int len) {
    // Since we're not going to have the GZIP encoding turned on,
    // we're not going to have an java.io.IOException thrown, so
    // we should not force the user to have to catch it.
    String encoded = null;
    try {
      encoded = encodeBytes(source, off, len, NO_OPTIONS);
    } catch (java.io.IOException ex) {
      assert false : ex.getMessage();
    } // end catch
    assert encoded != null;
    return encoded;
  } // end encodeBytes

  /**
   * Encodes a byte array into Base64 notation.
   * <p>
   * Example options:
   * 
   * <pre>
   *   GZIP: gzip-compresses object before encoding it.
   *   DO_BREAK_LINES: break lines at 76 characters
   *     <i>Note: Technically, this makes your encoding non-compliant.</i>
   * </pre>
   * <p>
   * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or
   * <p>
   * Example: <code>encodeBytes( myData, Base64.GZIP | Base64.DO_BREAK_LINES )</code>
   * 
   * 
   * <p>
   * As of v 2.3, if there is an error with the GZIP stream, the method will throw an java.io.IOException. <b>This is new to
   * v2.3!</b> In earlier versions, it just returned a null value, but in retrospect that's a pretty poor way to handle it.
   * </p>
   * 
   * 
   * @param source
   *          The data to convert
   * @param off
   *          Offset in array where conversion should begin
   * @param len
   *          Length of data to convert
   * @param options
   *          Specified options
   * @return The Base64-encoded data as a String
   * @see OBase64Utils#GZIP
   * @see OBase64Utils#DO_BREAK_LINES
   * @throws java.io.IOException
   *           if there is an error
   * @throws NullPointerException
   *           if source array is null
   * @throws IllegalArgumentException
   *           if source array, offset, or length are invalid
   * @since 2.0
   */
  public static String encodeBytes(final byte[] source, final int off, final int len, final int options)
      throws java.io.IOException {
    final byte[] encoded = encodeBytesToBytes(source, off, len, options);

    // Return value according to relevant encoding.
    try {
      return new String(encoded, PREFERRED_ENCODING);
    } // end try
    catch (java.io.UnsupportedEncodingException uue) {
      return new String(encoded);
    } // end catch

  } // end encodeBytes

  /* ******** D E C O D I N G M E T H O D S ******** */

  /**
   * Similar to {@link #encodeBytes(byte[])} but returns a byte array instead of instantiating a String. This is more efficient if
   * you're working with I/O streams and have large data sets to encode.
   * 
   * 
   * @param source
   *          The data to convert
   * @return The Base64-encoded data as a byte[] (of ASCII characters)
   * @throws NullPointerException
   *           if source array is null
   * @since 2.3.1
   */
  public static byte[] encodeBytesToBytes(byte[] source) {
    byte[] encoded = null;
    try {
      encoded = encodeBytesToBytes(source, 0, source.length, OBase64Utils.NO_OPTIONS);
    } catch (java.io.IOException ex) {
      assert false : "IOExceptions only come from GZipping, which is turned off: " + ex.getMessage();
    }
    return encoded;
  }

  /**
   * Similar to {@link #encodeBytes(byte[], int, int, int)} but returns a byte array instead of instantiating a String. This is more
   * efficient if you're working with I/O streams and have large data sets to encode.
   * 
   * 
   * @param source
   *          The data to convert
   * @param off
   *          Offset in array where conversion should begin
   * @param len
   *          Length of data to convert
   * @param options
   *          Specified options
   * @return The Base64-encoded data as a String
   * @see OBase64Utils#GZIP
   * @see OBase64Utils#DO_BREAK_LINES
   * @throws java.io.IOException
   *           if there is an error
   * @throws NullPointerException
   *           if source array is null
   * @throws IllegalArgumentException
   *           if source array, offset, or length are invalid
   * @since 2.3.1
   */
  public static byte[] encodeBytesToBytes(byte[] source, int off, int len, int options) throws java.io.IOException {

    if (source == null) {
      throw new NullPointerException("Cannot serialize a null array.");
    } // end if: null

    if (off < 0) {
      throw new IllegalArgumentException("Cannot have negative offset: " + off);
    } // end if: off < 0

    if (len < 0) {
      throw new IllegalArgumentException("Cannot have length offset: " + len);
    } // end if: len < 0

    if (off + len > source.length) {
      throw new IllegalArgumentException(
          String.format("Cannot have offset of %d and length of %d with array of length %d", off, len, source.length));
    } // end if: off < 0

    // Compress?
    if ((options & GZIP) != 0) {
      java.io.ByteArrayOutputStream baos = null;
      java.util.zip.GZIPOutputStream gzos = null;
      OBase64Utils.OutputStream b64os = null;

      try {
        // GZip -> Base64 -> ByteArray
        baos = new java.io.ByteArrayOutputStream();
        b64os = new OBase64Utils.OutputStream(baos, ENCODE | options);
        gzos = new java.util.zip.GZIPOutputStream(b64os, 16384); // 16KB

        gzos.write(source, off, len);
        gzos.close();
      } // end try
      catch (java.io.IOException e) {
        // Catch it and then throw it immediately so that
        // the finally{} block is called for cleanup.
        throw e;
      } // end catch
      finally {
        try {
          gzos.close();
        } catch (Exception e) {
        }
        try {
          b64os.close();
        } catch (Exception e) {
        }
        try {
          baos.close();
        } catch (Exception e) {
        }
      } // end finally

      return baos.toByteArray();
    } // end if: compress

    // Else, don't compress. Better not to use streams at all then.
    else {
      boolean breakLines = (options & DO_BREAK_LINES) != 0;

      // int len43 = len * 4 / 3;
      // byte[] outBuff = new byte[ ( len43 ) // Main 4:3
      // + ( (len % 3) > 0 ? 4 : 0 ) // Account for padding
      // + (breakLines ? ( len43 / MAX_LINE_LENGTH ) : 0) ]; // New lines
      // Try to determine more precisely how big the array needs to be.
      // If we get it right, we don't have to do an array copy, and
      // we save a bunch of memory.
      int encLen = (len / 3) * 4 + (len % 3 > 0 ? 4 : 0); // Bytes needed for actual encoding
      if (breakLines) {
        encLen += encLen / MAX_LINE_LENGTH; // Plus extra newline characters
      }
      byte[] outBuff = new byte[encLen];

      int d = 0;
      int e = 0;
      int len2 = len - 2;
      int lineLength = 0;
      for (; d < len2; d += 3, e += 4) {
        encode3to4(source, d + off, 3, outBuff, e, options);

        lineLength += 4;
        if (breakLines && lineLength >= MAX_LINE_LENGTH) {
          outBuff[e + 4] = NEW_LINE;
          e++;
          lineLength = 0;
        } // end if: end of line
      } // en dfor: each piece of array

      if (d < len) {
        encode3to4(source, d + off, len - d, outBuff, e, options);
        e += 4;
      } // end if: some padding needed

      // Only resize array if we didn't guess it right.
      if (e <= outBuff.length - 1) {
        // If breaking lines and the last byte falls right at
        // the line length (76 bytes per line), there will be
        // one extra byte, and the array will need to be resized.
        // Not too bad of an estimate on array size, I'd say.
        byte[] finalOut = new byte[e];
        System.arraycopy(outBuff, 0, finalOut, 0, e);
        // System.err.println("Having to resize array from " + outBuff.length + " to " + e );
        return finalOut;
      } else {
        // System.err.println("No need to resize array.");
        return outBuff;
      }

    } // end else: don't compress

  } // end encodeBytesToBytes

  /**
   * Decodes four bytes from array <var>source</var> and writes the resulting bytes (up to three of them) to <var>destination</var>.
   * The source and destination arrays can be manipulated anywhere along their length by specifying <var>srcOffset</var> and
   * <var>destOffset</var>. This method does not check to make sure your arrays are large enough to accomodate <var>srcOffset</var>
   * + 4 for the <var>source</var> array or <var>destOffset</var> + 3 for the <var>destination</var> array. This method returns the
   * actual number of bytes that were converted from the Base64 encoding.
   * <p>
   * This is the lowest level of the decoding methods with all possible parameters.
   * </p>
   * 
   * 
   * @param source
   *          the array to convert
   * @param srcOffset
   *          the index where conversion begins
   * @param destination
   *          the array to hold the conversion
   * @param destOffset
   *          the index where output will be put
   * @param options
   *          alphabet type is pulled from this (standard, url-safe, ordered)
   * @return the number of decoded bytes converted
   * @throws NullPointerException
   *           if source or destination arrays are null
   * @throws IllegalArgumentException
   *           if srcOffset or destOffset are invalid or there is not enough room in the array.
   * @since 1.3
   */
  private static int decode4to3(byte[] source, int srcOffset, byte[] destination, int destOffset, int options) {

    // Lots of error checking and exception throwing
    if (source == null) {
      throw new NullPointerException("Source array was null.");
    } // end if
    if (destination == null) {
      throw new NullPointerException("Destination array was null.");
    } // end if
    if (srcOffset < 0 || srcOffset + 3 >= source.length) {
      throw new IllegalArgumentException(String
          .format("Source array with length %d cannot have offset of %d and still process four bytes", source.length, srcOffset));
    } // end if
    if (destOffset < 0 || destOffset + 2 >= destination.length) {
      throw new IllegalArgumentException(String.format(
          "Destination array with length %d cannot have offset of %d and still store three bytes", destination.length, destOffset));
    } // end if

    byte[] DECODABET = getDecodabet(options);

    // Example: Dk==
    if (source[srcOffset + 2] == EQUALS_SIGN) {
      // Two ways to do the same thing. Don't know which way I like best.
      // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 )
      // | ( ( DECODABET[ source[ srcOffset + 1] ] << 24 ) >>> 12 );
      int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18) | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12);

      destination[destOffset] = (byte) (outBuff >>> 16);
      return 1;
    }

    // Example: DkL=
    else if (source[srcOffset + 3] == EQUALS_SIGN) {
      // Two ways to do the same thing. Don't know which way I like best.
      // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 )
      // | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
      // | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 );
      int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18) | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12)
          | ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6);

      destination[destOffset] = (byte) (outBuff >>> 16);
      destination[destOffset + 1] = (byte) (outBuff >>> 8);
      return 2;
    }

    // Example: DkLE
    else {
      // Two ways to do the same thing. Don't know which way I like best.
      // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 )
      // | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
      // | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 )
      // | ( ( DECODABET[ source[ srcOffset + 3 ] ] << 24 ) >>> 24 );
      int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18) | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12)
          | ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6) | ((DECODABET[source[srcOffset + 3]] & 0xFF));

      destination[destOffset] = (byte) (outBuff >> 16);
      destination[destOffset + 1] = (byte) (outBuff >> 8);
      destination[destOffset + 2] = (byte) (outBuff);

      return 3;
    }
  } // end decodeToBytes

  /**
   * Low-level access to decoding ASCII characters in the form of a byte array. <strong>Ignores GUNZIP option, if it's set.</strong>
   * This is not generally a recommended method, although it is used internally as part of the decoding process. Special case: if
   * len = 0, an empty array is returned. Still, if you need more speed and reduced memory footprint (and aren't gzipping), consider
   * this method.
   * 
   * @param source
   *          The Base64 encoded data
   * @return decoded data
   * @since 2.3.1
   */
  public static byte[] decode(byte[] source) throws java.io.IOException {
    byte[] decoded = null;
    // try {
    decoded = decode(source, 0, source.length, OBase64Utils.NO_OPTIONS);
    // } catch( java.io.IOException ex ) {
    // assert false : "IOExceptions only come from GZipping, which is turned off: " + ex.getMessage();
    // }
    return decoded;
  }

  /**
   * Low-level access to decoding ASCII characters in the form of a byte array. <strong>Ignores GUNZIP option, if it's set.</strong>
   * This is not generally a recommended method, although it is used internally as part of the decoding process. Special case: if
   * len = 0, an empty array is returned. Still, if you need more speed and reduced memory footprint (and aren't gzipping), consider
   * this method.
   * 
   * @param source
   *          The Base64 encoded data
   * @param off
   *          The offset of where to begin decoding
   * @param len
   *          The length of characters to decode
   * @param options
   *          Can specify options such as alphabet type to use
   * @return decoded data
   * @since 1.3
   */
  public static byte[] decode(byte[] source, int off, int len, int options) {

    // Lots of error checking and exception throwing
    if (source == null) {
      throw new NullPointerException("Cannot decode null source array.");
    } // end if
    if (off < 0 || off + len > source.length) {
      throw new IllegalArgumentException(
          String.format("Source array with length %d cannot have offset of %d and process %d bytes", source.length, off, len));
    } // end if

    if (len == 0) {
      return OCommonConst.EMPTY_BYTE_ARRAY;
    } else if (len < 4) {
      throw new IllegalArgumentException(
          "Base64-encoded string must have at least four characters, but length specified was " + len);
    } // end if

    byte[] DECODABET = getDecodabet(options);

    int len34 = len * 3 / 4; // Estimate on array size
    byte[] outBuff = new byte[len34]; // Upper limit on size of output
    int outBuffPosn = 0; // Keep track of where we're writing

    byte[] b4 = new byte[4]; // Four byte buffer from source, eliminating white space
    int b4Posn = 0; // Keep track of four byte input buffer
    int i = 0; // Source array counter
    byte sbiDecode = 0; // Special value from DECODABET

    for (i = off; i < off + len; i++) { // Loop through source

      sbiDecode = DECODABET[source[i] & 0xFF];

      // White space, Equals sign, or legit Base64 character
      // Note the values such as -5 and -9 in the
      // DECODABETs at the top of the file.
      if (sbiDecode >= WHITE_SPACE_ENC) {
        if (sbiDecode >= EQUALS_SIGN_ENC) {
          b4[b4Posn++] = source[i]; // Save non-whitespace
          if (b4Posn > 3) { // Time to decode?
            outBuffPosn += decode4to3(b4, 0, outBuff, outBuffPosn, options);
            b4Posn = 0;

            // If that was the equals sign, break out of 'for' loop
            if (source[i] == EQUALS_SIGN) {
              break;
            } // end if: equals sign
          } // end if: quartet built
        } // end if: equals sign or better
      } // end if: white space, equals sign or better
      else {
        // There's a bad input character in the Base64 stream.
        throw new OIOException(String.format("Bad Base64 input character decimal %d in array position %d", (source[i]) & 0xFF, i));
      } // end else:
    } // each input character

    byte[] out = new byte[outBuffPosn];
    System.arraycopy(outBuff, 0, out, 0, outBuffPosn);
    return out;
  } // end decode

  /**
   * Decodes data from Base64 notation, automatically detecting gzip-compressed data and decompressing it.
   * 
   * @param s
   *          the string to decode
   * @return the decoded data
   * @since 1.4
   */
  public static byte[] decode(String s) {
    return decode(s, DONT_GUNZIP);
  }

  /**
   * Decodes data from Base64 notation, automatically detecting gzip-compressed data and decompressing it.
   * 
   * @param s
   *          the string to decode
   * @param options
   *          encode options such as URL_SAFE
   * @return the decoded data
   * @throws NullPointerException
   *           if <tt>s</tt> is null
   * @since 1.4
   */
  public static byte[] decode(String s, int options) {

    if (s == null) {
      throw new NullPointerException("Input string was null.");
    } // end if

    byte[] bytes;
    try {
      bytes = s.getBytes(PREFERRED_ENCODING);
    } // end try
    catch (java.io.UnsupportedEncodingException uee) {
      bytes = s.getBytes();
    } // end catch
    // </change>

    // Decode
    bytes = decode(bytes, 0, bytes.length, options);

    // Check to see if it's gzip-compressed
    // GZIP Magic Two-Byte Number: 0x8b1f (35615)
    boolean dontGunzip = (options & DONT_GUNZIP) != 0;
    if ((bytes != null) && (bytes.length >= 4) && (!dontGunzip)) {

      int head = (bytes[0] & 0xff) | ((bytes[1] << 8) & 0xff00);
      if (java.util.zip.GZIPInputStream.GZIP_MAGIC == head) {
        java.io.ByteArrayInputStream bais = null;
        java.util.zip.GZIPInputStream gzis = null;
        java.io.ByteArrayOutputStream baos = null;
        byte[] buffer = new byte[2048];
        int length = 0;

        try {
          baos = new java.io.ByteArrayOutputStream();
          bais = new java.io.ByteArrayInputStream(bytes);
          gzis = new java.util.zip.GZIPInputStream(bais, 16384); // 16KB

          while ((length = gzis.read(buffer)) >= 0) {
            baos.write(buffer, 0, length);
          } // end while: reading input

          // No error? Get new bytes.
          bytes = baos.toByteArray();

        } // end try
        catch (java.io.IOException e) {
          OLogManager.instance().error(null, "Error on decoding Base64", e);
          // Just return originally-decoded bytes
        } // end catch
        finally {
          try {
            baos.close();
          } catch (Exception e) {
          }
          try {
            gzis.close();
          } catch (Exception e) {
          }
          try {
            bais.close();
          } catch (Exception e) {
          }
        } // end finally

      } // end if: gzipped
    } // end if: bytes.length >= 2

    return bytes;
  } // end decode

  /**
   * Attempts to decode Base64 data and deserialize a Java Object within. Returns <tt>null</tt> if there was an error.
   * 
   * @param encodedObject
   *          The Base64 data to decode
   * @return The decoded and deserialized object
   * @throws NullPointerException
   *           if encodedObject is null
   * @throws java.io.IOException
   *           if there is a general error
   * @throws ClassNotFoundException
   *           if the decoded object is of a class that cannot be found by the JVM
   * @since 1.5
   */
  public static Object decodeToObject(String encodedObject) throws java.io.IOException, java.lang.ClassNotFoundException {
    return decodeToObject(encodedObject, NO_OPTIONS, null);
  }

  /**
   * Attempts to decode Base64 data and deserialize a Java Object within. Returns <tt>null</tt> if there was an error. If
   * <tt>loader</tt> is not null, it will be the class loader used when deserializing.
   * 
   * @param encodedObject
   *          The Base64 data to decode
   * @param options
   *          Various parameters related to decoding
   * @param loader
   *          Optional class loader to use in deserializing classes.
   * @return The decoded and deserialized object
   * @throws NullPointerException
   *           if encodedObject is null
   * @throws java.io.IOException
   *           if there is a general error
   * @throws ClassNotFoundException
   *           if the decoded object is of a class that cannot be found by the JVM
   * @since 2.3.4
   */
  public static Object decodeToObject(String encodedObject, int options, final ClassLoader loader)
      throws java.io.IOException, java.lang.ClassNotFoundException {

    // Decode and gunzip if necessary
    byte[] objBytes = decode(encodedObject, options);

    java.io.ByteArrayInputStream bais = null;
    java.io.ObjectInputStream ois = null;
    Object obj = null;

    try {
      bais = new java.io.ByteArrayInputStream(objBytes);

      // If no custom class loader is provided, use Java's builtin OIS.
      if (loader == null) {
        ois = new java.io.ObjectInputStream(bais);
      } // end if: no loader provided

      // Else make a customized object input stream that uses
      // the provided class loader.
      else {
        ois = new java.io.ObjectInputStream(bais) {
          @Override
          public Class<?> resolveClass(java.io.ObjectStreamClass streamClass) throws java.io.IOException, ClassNotFoundException {
            Class<?> c = Class.forName(streamClass.getName(), false, loader);
            if (c == null) {
              return super.resolveClass(streamClass);
            } else {
              return c; // Class loader knows of this class.
            } // end else: not null
          } // end resolveClass
        }; // end ois
      } // end else: no custom class loader

      obj = ois.readObject();
    } // end try
    catch (java.io.IOException e) {
      throw e; // Catch and throw in order to execute finally{}
    } // end catch
    catch (java.lang.ClassNotFoundException e) {
      throw e; // Catch and throw in order to execute finally{}
    } // end catch
    finally {
      try {
        bais.close();
      } catch (Exception e) {
      }
      try {
        ois.close();
      } catch (Exception e) {
      }
    } // end finally

    return obj;
  } // end decodeObject

  /**
   * Convenience method for encoding data to a file.
   * 
   * <p>
   * As of v 2.3, if there is a error, the method will throw an java.io.IOException. <b>This is new to v2.3!</b> In earlier
   * versions, it just returned false, but in retrospect that's a pretty poor way to handle it.
   * </p>
   * 
   * @param dataToEncode
   *          byte array of data to encode in base64 form
   * @param filename
   *          Filename for saving encoded data
   * @throws java.io.IOException
   *           if there is an error
   * @throws NullPointerException
   *           if dataToEncode is null
   * @since 2.1
   */
  public static void encodeToFile(byte[] dataToEncode, String filename) throws java.io.IOException {

    if (dataToEncode == null) {
      throw new NullPointerException("Data to encode was null.");
    } // end iff

    OBase64Utils.OutputStream bos = null;
    try {
      bos = new OBase64Utils.OutputStream(new java.io.FileOutputStream(filename), OBase64Utils.ENCODE);
      bos.write(dataToEncode);
    } // end try
    catch (java.io.IOException e) {
      throw e; // Catch and throw to execute finally{} block
    } // end catch: java.io.IOException
    finally {
      try {
        bos.close();
      } catch (Exception e) {
      }
    } // end finally

  } // end encodeToFile

  /**
   * Convenience method for decoding data to a file.
   * 
   * <p>
   * As of v 2.3, if there is a error, the method will throw an java.io.IOException. <b>This is new to v2.3!</b> In earlier
   * versions, it just returned false, but in retrospect that's a pretty poor way to handle it.
   * </p>
   * 
   * @param dataToDecode
   *          Base64-encoded data as a string
   * @param filename
   *          Filename for saving decoded data
   * @throws java.io.IOException
   *           if there is an error
   * @since 2.1
   */
  public static void decodeToFile(String dataToDecode, String filename) throws java.io.IOException {

    OBase64Utils.OutputStream bos = null;
    try {
      bos = new OBase64Utils.OutputStream(new java.io.FileOutputStream(filename), OBase64Utils.DECODE);
      bos.write(dataToDecode.getBytes(PREFERRED_ENCODING));
    } // end try
    catch (java.io.IOException e) {
      throw e; // Catch and throw to execute finally{} block
    } // end catch: java.io.IOException
    finally {
      try {
        bos.close();
      } catch (Exception e) {
      }
    } // end finally

  } // end decodeToFile

  /**
   * Convenience method for reading a base64-encoded file and decoding it.
   * 
   * <p>
   * As of v 2.3, if there is a error, the method will throw an java.io.IOException. <b>This is new to v2.3!</b> In earlier
   * versions, it just returned false, but in retrospect that's a pretty poor way to handle it.
   * </p>
   * 
   * @param filename
   *          Filename for reading encoded data
   * @return decoded byte array
   * @throws java.io.IOException
   *           if there is an error
   * @since 2.1
   */
  public static byte[] decodeFromFile(String filename) throws java.io.IOException {

    byte[] decodedData = null;
    OBase64Utils.InputStream bis = null;
    try {
      // Set up some useful variables
      java.io.File file = new java.io.File(filename);
      byte[] buffer = null;
      int length = 0;
      int numBytes = 0;

      // Check for size of file
      if (file.length() > Integer.MAX_VALUE) {
        throw new java.io.IOException("File is too big for this convenience method (" + file.length() + " bytes).");
      } // end if: file too big for int index
      buffer = new byte[(int) file.length()];

      // Open a stream
      bis = new OBase64Utils.InputStream(new java.io.BufferedInputStream(new java.io.FileInputStream(file)), OBase64Utils.DECODE);

      // Read until done
      while ((numBytes = bis.read(buffer, length, 4096)) >= 0) {
        length += numBytes;
      } // end while

      // Save in a variable to return
      decodedData = new byte[length];
      System.arraycopy(buffer, 0, decodedData, 0, length);

    } // end try
    catch (java.io.IOException e) {
      throw e; // Catch and release to execute finally{}
    } // end catch: java.io.IOException
    finally {
      try {
        bis.close();
      } catch (Exception e) {
      }
    } // end finally

    return decodedData;
  } // end decodeFromFile

  /**
   * Convenience method for reading a binary file and base64-encoding it.
   * 
   * <p>
   * As of v 2.3, if there is a error, the method will throw an java.io.IOException. <b>This is new to v2.3!</b> In earlier
   * versions, it just returned false, but in retrospect that's a pretty poor way to handle it.
   * </p>
   * 
   * @param filename
   *          Filename for reading binary data
   * @return base64-encoded string
   * @throws java.io.IOException
   *           if there is an error
   * @since 2.1
   */
  public static String encodeFromFile(String filename) throws java.io.IOException {

    String encodedData = null;
    OBase64Utils.InputStream bis = null;
    try {
      // Set up some useful variables
      java.io.File file = new java.io.File(filename);
      byte[] buffer = new byte[Math.max((int) (file.length() * 1.4 + 1), 40)]; // Need max() for math on small files (v2.2.1); Need
                                                                               // +1 for a few corner cases (v2.3.5)
      int length = 0;
      int numBytes = 0;

      // Open a stream
      bis = new OBase64Utils.InputStream(new java.io.BufferedInputStream(new java.io.FileInputStream(file)), OBase64Utils.ENCODE);

      // Read until done
      while ((numBytes = bis.read(buffer, length, 4096)) >= 0) {
        length += numBytes;
      } // end while

      // Save in a variable to return
      encodedData = new String(buffer, 0, length, OBase64Utils.PREFERRED_ENCODING);

    } // end try
    catch (java.io.IOException e) {
      throw e; // Catch and release to execute finally{}
    } // end catch: java.io.IOException
    finally {
      try {
        bis.close();
      } catch (Exception e) {
      }
    } // end finally

    return encodedData;
  } // end encodeFromFile

  /* ******** I N N E R C L A S S I N P U T S T R E A M ******** */

  /**
   * Reads <tt>infile</tt> and encodes it to <tt>outfile</tt>.
   * 
   * @param infile
   *          Input file
   * @param outfile
   *          Output file
   * @throws java.io.IOException
   *           if there is an error
   * @since 2.2
   */
  public static void encodeFileToFile(String infile, String outfile) throws java.io.IOException {

    String encoded = OBase64Utils.encodeFromFile(infile);
    java.io.OutputStream out = null;
    try {
      out = new java.io.BufferedOutputStream(new java.io.FileOutputStream(outfile));
      out.write(encoded.getBytes("US-ASCII")); // Strict, 7-bit output.
    } // end try
    catch (java.io.IOException e) {
      throw e; // Catch and release to execute finally{}
    } // end catch
    finally {
      try {
        out.close();
      } catch (Exception ex) {
      }
    } // end finally
  } // end encodeFileToFile

  /* ******** I N N E R C L A S S O U T P U T S T R E A M ******** */

  /**
   * Reads <tt>infile</tt> and decodes it to <tt>outfile</tt>.
   * 
   * @param infile
   *          Input file
   * @param outfile
   *          Output file
   * @throws java.io.IOException
   *           if there is an error
   * @since 2.2
   */
  public static void decodeFileToFile(String infile, String outfile) throws java.io.IOException {

    byte[] decoded = OBase64Utils.decodeFromFile(infile);
    java.io.OutputStream out = null;
    try {
      out = new java.io.BufferedOutputStream(new java.io.FileOutputStream(outfile));
      out.write(decoded);
    } // end try
    catch (java.io.IOException e) {
      throw e; // Catch and release to execute finally{}
    } // end catch
    finally {
      try {
        out.close();
      } catch (Exception ex) {
      }
    } // end finally
  } // end decodeFileToFile

} // end class Base64
